KeNHA Announces Temporary Closure of Nairobi Southern Bypass on Sunday

The Kenya National Highways Authority (KeNHA) has announced the temporary closure of a section of the Nairobi Southern Bypass to facilitate the 2026 Standard Chartered Nairobi Marathon.

In a notice on Monday, October 19, the authority said the closure would affect the stretch between Ole Sereni Interchange and Kikuyu Town from midnight on Saturday, October 24, to 2pm on Sunday, October 25.

"The Kenya National Highways Authority (KeNHA) wishes to notify the Public that there will be a temporary closure of Nairobi Southern Bypass from Ole Sereni Interchange to Kikuyu Town on Saturday, October 24, 2026 at Midnight to Sunday October 25, 2026 at 2.00pm," the notice read.

KeNHA advised motorists travelling between the affected areas to use alternative routes during the closure.

"Motorists are advised to use Mombasa Road (A8) from Ole Sereni Interchange through Uhuru Highway, and vice versa, as the alternative route. 

"All road users are further advised to follow the traffic signs and guidance as directed by traffic marshals and Police," the notice added.

KeNHA outlined several traffic diversions to guide motorists travelling to and from Kikuyu, Dagoretti, Karen, Langata Road and Mombasa Road during the marathon.

Motorists travelling from Kikuyu to Dagoretti will be able to access Dagoretti through the Southern Bypass.

Those travelling from Karen, specifically the Kaninde area, to Kikuyu will also be able to use the Southern Bypass through Dagoretti Road.

Between noon and 1:30pm on Sunday, October 25, motorists travelling from Kikuyu to Mombasa Road through the Southern Bypass will be required to use Waiyaki Way.

Drivers travelling from Dagoretti to Mombasa Road through the bypass will be advised to use Waiyaki Way or take Ngong Road and Mbagathi Way.

Motorists travelling from Lenana along Ngong Road to Kikuyu through the Southern Bypass will be required to use Waiyaki Way through Naivasha Road or James Gichuru Road.

Those travelling from Langata Road near Galleria Mall to Kikuyu will be directed to use Langata Road through Karen.

Trailers and lorries travelling from Waiyaki Way to Mombasa Road through the Southern Bypass will also be required to use Waiyaki Way as the designated diversion.

The notice also listed traffic diversions affecting Karas, Shopping Centre, Langata Road near Galleria Mall, Langata Road near the CDF offices, Mombasa Road and Likoni Road between noon and 12:30pm on Sunday. 

This comes a week after KeNHA announced the temporary closure of a section of the Mayoni-Bungoma (B139) Road for three months.

In a notice on Friday, October 9, the authority said the closure will take effect on Friday, October 16, and remain in place until Friday, January 15, 2027.

"The Kenya National Highways Authority (KeNHA) notifies the public that a section of Mayoni – Bungoma (B139) Road will be closed at Km 2+100 from Friday 16th October, 2026 to Friday 15th January 2027," the notice read.

KeNHA explained that the closure was necessary to allow construction works to proceed on the affected section of the highway.

"This closure is to allow for construction of a box culvert on this road section," the notice added.

KeNHA advised motorists planning to use the road during the closure period to follow the designated diversion and adhere to the traffic management arrangements put in place.

The authority also urged drivers to cooperate with police officers and traffic marshals deployed at the site to ensure smooth traffic movement and safety during the construction period.

"All motorists intending to use Mayoni - Bungoma (B139) Road will use the provided diversion and follow the proposed traffic management plan as well as cooperate with the police and traffic marshals on site," the notice further read.